30 



in the middle of each series are axillary and bear quaternary 

 radials. There are, therefore, thirty arms and thirty ambula- 

 cral openings to the vault in this species, as shown by our 

 specimens. 



The interradial areas all graduate up into the vault and over 

 the ambulacral channels so as to leave no evidence of any di- 

 viding line between the vault and calyx. In the regular areas, 

 one large plate is followed by two, in the second range, three, 

 in the third range, and five, in the fourth range, that connect 

 with the plates of the vault. In the azygous area the first 

 plate is in line with the first primary radials and like them, 

 except somewhat smaller. It is followed by two plates, in the 

 second range, three, in the third range, five, in the fourth 

 range, and eight, in the fifth range that connect with the 

 plates of the vault. This area is very wide between the pro- 

 jecting radial series. 



The vault is elevated over the ambulacral channels so that a 

 transverse section of the radial series is subquadrate. It is 

 convex toward the center where it bears a proboscis. It is 

 covered with convex, polygonal plates of very unequal size. 

 No ovarian pores have been detected. 



This species is from rocks of a higher geological range than 

 any heretofore described, but a true Steganocrinus, however, 

 distantly related to other species. 



Found by Dr. M. N. Elrod, in the St. Louis Group, at Sper- 

 gen Hill, Indiana, and now in the collection of Wm. P. E. Gurley. 



STROTOCRINUS ORNATUS, n. Sp. 



Plate II, Fig. 12, azygous view; Fig. 13, right lateral view; 

 Fig. 14, summit view. 



Species rather below medium size, as shown by our speci- 

 mens. Calyx moderately truncated below, obconoidal as high 

 as the top of the third primary radials, and then abruptly ex- 

 panded, in the form of a flattened rim, that cuts off all con- 

 nection of the interradial areas with the vault, as is usual in 

 this genus. Primary radials transvesly nodose, interradials 

 nodose, and surface of all of them radiately sculptured; above 

 the primary radials, the radial ridges are somewhat angular at 

 first but rounded above. 



Basals wider than high, stand upright, deeply beveled at 

 the sutures and each extends a cuneiform end below the point 

 of the columnar attachment. First primary radials about as 



